D — https://khanacademy.org | BeaverCheck Audit

Site Health

Score: 68 / 100

Based on 8 categories, 0 sections

Room to improve — your 12.3s load time is above Google's 2.5s 'Good' threshold.

Good foundation, but a few gaps could be exploited.

Several issues make your site difficult for assistive technology users.

Solid SEO basics — a few optimizations could boost rankings.

Good server performance with room for optimization.

Mostly compliant — a few items need attention.

Missing metadata means poor previews on social media and search.

Heavier than average — reducing page weight saves energy and bandwidth.

How is this calculated?

The overall score is a weighted average of individual category scores. Categories with more impact on user experience and security carry more weight.

Performance 25%Security 25%Accessibility 15%SEO 10%Infrastructure 10%Compliance 8%Content 5%Sustainability 2%

Weights reflect general web best practices. Individual needs may differ.

How the composite score is calculated

How you compare

Amazon Route 53 sites average 72

At average

Better than 7% of Amazon Route 53 sites See full Amazon Route 53 benchmark →

Apple sites average 73

At average

Better than 5% of Apple sites See full Apple benchmark →

Top Priorities (5)

Content-Security-Policy header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers

HSTS header is missing

Security gaps expose your site and users to attacks, eroding trust.

Security › Security Headers

No Content-Security-Policy header found

Security gaps expose your site and users to attacks, eroding trust.

Security › Content Security Policy

Page weighs 7.3 MB (4.1 MB transferred)

Performance issues directly impact user engagement and conversion rates.

Performance › Page Weight Budget

No <main> landmark found

Accessibility issues exclude users with disabilities — up to 15% of your potential audience.

Accessibility › Landmark Structure

View fix priority matrix

Fix Priority Matrix

5 findings

Impact

Quick Wins

High impact, low effort — start here.

Strategic

High impact, requires investment.

Easy Improvements

Small gains, minimal effort.

Nothing in this quadrant — good news.

Deprioritize

Low impact, high effort — do last.

Nothing in this quadrant — good news.

← Low effort High effort →

Embed this badge

Markdown

[![BeaverCheck](https://beavercheck.com/badge?url=https%3A%2F%2Fkhanacademy.org)](https://beavercheck.com/results/34d2356f-b8b0-42b4-98b8-9a3bfb5b7aa6)

HTML

<a href="https://beavercheck.com/results/34d2356f-b8b0-42b4-98b8-9a3bfb5b7aa6"><img src="https://beavercheck.com/badge?url=https%3A%2F%2Fkhanacademy.org" alt="BeaverCheck Score"></a>

Image URL

https://beavercheck.com/badge?url=https%3A%2F%2Fkhanacademy.org

This badge auto-updates with your latest scan result.

What fixing these means

Your site has several issues that may be affecting user experience and business outcomes. Your LCP of 12.3s exceeds Google's 2.5s 'Good' threshold and the 1 performance issue below directly contributes to it. Accessibility issues exclude users who rely on assistive technology — an estimated 15% of your potential audience. Addressing the critical issues below would have the most immediate impact on your user trust.

3 security gaps detected — browsers may warn visitors about your site.

Your LCP is 12.3s — fixing the 1 performance critical could bring it under Google's 2.5s 'Good' threshold.

1 accessibility issue excludes users who rely on assistive technology.

Could reach Estimate based on resolving critical issues

Return on Investment

$500 investment → $2,929/month returns + USD 157,500 risk avoided

Payback period: < 1 month First-year ROI: +6930%

Investment

$500

5h · 5 findings

Monthly returns

$2,929 /mo

~$35,150 / year

Conversions recovered $2,928
Bandwidth savings $1.04

Regulatory risk avoided

USD 157,500

if kept compliant

ADA Title III USD 150,000
CCPA/CPRA USD 7,500

Payback period

0 12mo 24mo

$150 — in quick wins — start here for the fastest payback

Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.

Full methodology & sources

Estimated Remediation Cost

$500

5.0 developer hours at $100/hr

Based on United States rates ($100/hr)

Quick wins

$150 3 fixes in ~90 minutes

Start here for the best return on investment

Cost by category

Cost by effort level

Adjust assumptions

Custom rate

$ /hr

Rates reflect fully-loaded developer cost including overhead

How developer rates are sourced

What Inaction Is Costing You

$13,126 / month at risk

~$157,513 / year if left unfixed

Compliance Risk

$157,500

ADA Title IIICCPA/CPRA

No privacy policy link detected
CCPA/CPRA: USD 2,500 – USD 7,500
Trackers detected but no cookie policy found
CCPA/CPRA: USD 2,500 – USD 7,500
Trackers detected but no privacy policy found
CCPA/CPRA: USD 2,500 – USD 7,500

+5 more

Bandwidth Waste

$1.04 /mo

13044.5 MB/mo × 0.080 USD/GB

Optimize transfer: save ~1.3 MB per page load
Saves $1.04/mo

Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.

Compliance methodology · SEO assumptions · Bandwidth model

Your performance is already good — improvements may show diminishing returns

Monthly visitors

Unique monthly visitors from your analytics

Conversion rate (%)

Purchases, signups, or key actions

Avg. order value

Optional — for revenue estimation

additional conversions/month

more engaged visitors from reduced bounce

potential monthly revenue

Current bounce (est.)

After fixes (est.)

Estimated bounce reduction

Fix 5 critical issues to capture this value

How this is calculated

Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.

Your site's LCP: → estimated after fixes.

These are estimates based on industry research — actual results vary

Bounce-rate model & assumptions

Your data stays in your browser — nothing is sent to our servers

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Lighthouse Scores

Industry-standard audits powered by Google Lighthouse.

Performance

100

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

7.62 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

12.29 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

760 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.744

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

7.62 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

12.45 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Most users today run browsers that natively support ES6+, async/await, optional chaining, and the rest of modern JavaScript. Transpiling to ES5 'just in case' adds 20-40% to your bundle for no benefit. Configure your build to target a modern browserslist, or ship a differential bundle pair (modern + legacy) with the module/nomodule pattern.

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]

items: [map[node:map[type:text value:Total] score:0.7443250000000002] map[node:map[boundingRect:map[bottom:828 height:766 left:0 right:412 top:62 width:412] lhId:page-1-DIV nodeLabel:Free to Use. Not Free to Make. "$1 = 100 minutes of learning. With less than … path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,DIV selector:div#app-shell-root > div._keh75d > div#donate-banner > div._1r6etbs snippet:<div class="_1r6etbs"> type:node] score:0.643783] map[node:map[boundingRect:map[bottom:813 height:419 left:0 right:379 top:394 width:379] lhId:page-3-DIV nodeLabel:Use of cookies Cookies are small files placed on your device that collect infor… path:1,HTML,1,BODY,4,DIV,1,DIV selector:body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk snippet:<div id="onetrust-banner-sdk" class="otFloatingRoundedCorner ot-bottom-left vertical-align-content ot-buttons-fw" tabindex="0" role="region" aria-label="Cookie banner" style="bottom: 1rem;"> type:node] score:0.003354] map[node:map[boundingRect:map[bottom:813 height:419 left:0 right:379 top:394 width:379] lhId:page-3-DIV nodeLabel:Use of cookies Cookies are small files placed on your device that collect infor… path:1,HTML,1,BODY,4,DIV,1,DIV selector:body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk snippet:<div id="onetrust-banner-sdk" class="otFloatingRoundedCorner ot-bottom-left vertical-align-content ot-buttons-fw" tabindex="0" role="region" aria-label="Cookie banner" style="bottom: 1rem;"> type:node] score:0.001862] map[node:map[boundingRect:map[bottom:813 height:419 left:0 right:379 top:394 width:379] lhId:page-3-DIV nodeLabel:Use of cookies Cookies are small files placed on your device that collect infor… path:1,HTML,1,BODY,4,DIV,1,DIV selector:body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk snippet:<div id="onetrust-banner-sdk" class="otFloatingRoundedCorner ot-bottom-left vertical-align-content ot-buttons-fw" tabindex="0" role="region" aria-label="Cookie banner" style="bottom: 1rem;"> type:node] score:0.00182] map[node:map[boundingRect:map[bottom:813 height:419 left:0 right:379 top:394 width:379] lhId:page-3-DIV nodeLabel:Use of cookies Cookies are small files placed on your device that collect infor… path:1,HTML,1,BODY,4,DIV,1,DIV selector:body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk snippet:<div id="onetrust-banner-sdk" class="otFloatingRoundedCorner ot-bottom-left vertical-align-content ot-buttons-fw" tabindex="0" role="region" aria-label="Cookie banner" style="bottom: 1rem;"> type:node] score:0.001787]]

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.

title: Preconnected origins

value: no origins were preconnected

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size	Duration
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	771.2 KiB	3.9 s
cdn.kastatic.org/khanacademy/khanacademy.753cf3d0cb0bd8f2.css	10.3 KiB	751 ms
cdn.kastatic.org/khanacademy/runtime.d2da0f18e591e2c0.js	13.6 KiB

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Request	Cache TTL	Transfer Size
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	86400.0 s	102.8 KiB
cdn.cookielaw.org/logos/static/ot_company_logo.png	86400.0 s	19.1 KiB
cdn.cookielaw.org/scripttemplates/otSDKStub.js	86400.0 s	9.1 KiB
/api/badges/download-on-the-app-store/black/en-us?release...	604800.0 s	11.3 KiB
cdn.cookielaw.org/logos/static/powered_by_logo.svg	86400.0 s	2.6 KiB

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Est Savings
cdn.kastatic.org/khanacademy/fonts/1cf13853095a62e2-LatoLatin-Bold.woff2	10 ms

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL	Resource Size	Est Savings
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/faces_collage_2@2x.png	666.4 KiB	623.2 KiB
Learners Teachers Parents Back `div._vtegui > div._e296pg > div#last-chance-lohp > div._18iqadbp`	cdn.kastatic.org/images/lohp/last_chance_collage@2x.png	373.4 KiB	177.1 KiB
div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1 `div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1`	cdn.kastatic.org/images/lohp/laptop_collage@2x.png	181.6 KiB	138.7 KiB
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/math-unicorn-donate-collage.png	158.3 KiB	120.7 KiB
div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1 `div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1`	cdn.kastatic.org/images/lohp/anjali-3.png	75.7 KiB	70.2 KiB
Get it on Google Play `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	cdn.kastatic.org/images/store-badges/google-play/en.png	5.9 KiB	5.3 KiB
Bill and Melinda Gates Foundation `div._51yg8mt > div._vuhkxie > div._1t9h51bq > img._55m9r6s`	cdn.kastatic.org/images/supporters-logos/gates-foundation-dark-gray@2x.png	8.2 KiB	5.2 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 798 ms

URL	Time Spent
khanacademy.org/	798 ms
www.khanacademy.org/	0.0 ms

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

Element	Layout shift score
Free to Use. Not Free to Make. "$1 = 100 minutes of learning. With less than … `div#app-shell-root > div._keh75d > div#donate-banner > div._1r6etbs`	0.644
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.003
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.002

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

Diagnostics

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

This is the Lighthouse audit fired when too much JS is shipped relative to what executes. The fix isn't a config flag — it requires bundle analysis (webpack-bundle-analyzer, rollup-plugin-visualizer), splitting routes into chunks, lazy-loading off-screen components, and removing unused dependencies. Fundamentally different from minification: minifying reduces byte count, this reduces what's downloaded at all.

Source: Google web.dev / Lighthouse

Estimated savings: 2.8 s 577.1 KiB

URL	Transfer Size	Est Savings
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	764.7 KiB	437.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-WSX5PBP	152.2 KiB	86.5 KiB
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	102.7 KiB	53.6 KiB

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to reduce Javascript execution time.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Total CPU Time	Script Evaluation	Script Parse
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	2.1 s	1.7 s	196 ms
www.khanacademy.org/	762 ms	36 ms	36 ms
Unattributable	631 ms	123 ms	0.0 ms
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	212 ms	136 ms	30 ms
www.googletagmanager.com/gtm.js?id=GTM-WSX5PBP	164 ms	128 ms	35 ms
cdn.kastatic.org/khanacademy/62538.3c089e819b2f9b6e.js	160 ms	136 ms	6.3 ms

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

Category	Time Spent
Script Evaluation	2.3 s
Other	863 ms
Style & Layout	457 ms
Script Parsing & Compilation	336 ms
Rendering	160 ms
Parse HTML & CSS	47 ms
Garbage Collection	28 ms

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reason	Failure type
Pages with cache-control:no-store header cannot enter back/forward cache.	Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.	Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.	Not actionable

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 17.2 KiB

URL	Transfer Size	Est Savings
#onetrust-banner-sdk{-ms-text-size-adjust:100%;-webkit-text-size-adjust:100%} …	19.6 KiB	17.2 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size
cdn.kastatic.org/ka-mpp/86b27ba2-df82-4a93-8cfb-b3a7e852da86.png	782.9 KiB
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	771.2 KiB
cdn.kastatic.org/images/lohp/faces_collage_2@2x.png	667.2 KiB
cdn.kastatic.org/images/lohp/last_chance_collage@2x.png	374.1 KiB
cdn.kastatic.org/images/lohp/boost-scores.png	210.6 KiB
cdn.kastatic.org/images/lohp/laptop_collage@2x.png	182.1 KiB
cdn.kastatic.org/images/lohp/math-unicorn-donate-collage.png	158.8 KiB
www.googletagmanager.com/gtm.js?id=GTM-WSX5PBP	152.6 KiB
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	102.8 KiB
cdn.kastatic.org/images/lohp/anjali-3.png	76.2 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/faces_collage_2@2x.png
div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1 `div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1`	cdn.kastatic.org/images/lohp/laptop_collage@2x.png
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/math-unicorn-donate-collage.png
Get it on Google Play `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	cdn.kastatic.org/images/store-badges/google-play/en.png
div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1 `div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1`	cdn.kastatic.org/images/lohp/anjali-3.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp`	cdn.kastatic.org/images/lohp/trusted_content_icon.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/personalized_learning_icon.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/empower_teachers_icon.png
Download on the App Store `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	/api/badges/download-on-the-app-store/black/en-us?release...

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Optimize DOM size

●Forced reflow

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●User Timing marks and measures 2 user timings

●Avoid long main-thread tasks 8 long tasks found

●Avoid non-composited animations 1 animated element found

●Network Requests

●Network Round Trip Times 180 ms

●Server Backend Latencies 230 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 260 ms

○INP breakdown

○LCP request discovery

100

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
English `div._s6za34 > div._1bvnlzk > div._6kyiev1 > button#:r4:`
cookie policy `div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text > a`

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

●ARIA attributes are used as specified for the element's role

●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links are distinguishable without relying on color.

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Document has a main landmark.

●Deprecated ARIA roles were not used

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements have accessible names

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<frame>` or `<iframe>` elements have a title

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.

○`[lang]` attributes have a valid value

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Identical links have the same purpose.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

100

Best Practices

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Use a strong HSTS policy

○Mitigate clickjacking with XFO or CSP

○Detected JavaScript libraries

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Content Best Practices

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destination	Link Text
cookiepedia.co.uk/giving-consent-to-cookies	More information

Format your HTML in a way that enables crawlers to better understand your app’s content.

Crawling and Indexing

If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Line #	Content	Error
1	`<!DOCTYPE html>`	`Syntax not understood`
2	`<html lang="en">`	`Syntax not understood`
3	`<head>`	`Syntax not understood`
4	`<meta`	`Syntax not understood`
5	`http-equiv="Content-Security-Policy"`	`Syntax not understood`
6	`content="default-src 'self'; img-src 'self' data:; media-src 'self' data:; object-src 'none'; style-src 'self' 'sha256-o4vzfmmUENEg4chMjjRP9EuW9ucGnGIGVdbl8d0SHQQ='; script-src 'self' 'sha256-a9bHdQGvRzDwDVzx8m+Rzw+0FHZad8L0zjtBwkxOIz4=';"`	`Unknown directive`
7	`/>`	`Syntax not understood`
8	`<link`	`Syntax not understood`
9	`href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/inter-var.woff2"`	`Syntax not understood`
10	`rel="preload"`	`Syntax not understood`
11	`as="font"`	`Syntax not understood`
12	`type="font/woff2"`	`Syntax not understood`
13	`crossorigin`	`Syntax not understood`
14	`/>`	`Syntax not understood`
15	`<link href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/styles.css" rel="stylesheet" />`	`Syntax not understood`
16	`<meta name="viewport" content="width=device-width, initial-scale=1" />`	`Syntax not understood`
17	`<title>Client Challenge</title>`	`Syntax not understood`
18	`<style>`	`Syntax not understood`
20	`font-size: 16px;`	`Unknown directive`
21	`font-family: 'Inter', sans-serif;`	`Unknown directive`
22	`margin-top: 10px;`	`Unknown directive`
23	`margin-left: 10px;`	`Unknown directive`
24	`display: none;`	`Unknown directive`
25	`}`	`Syntax not understood`
26	`</style>`	`Syntax not understood`
27	`</head>`	`Syntax not understood`
28	`<body>`	`Syntax not understood`
29	`<noscript>`	`Syntax not understood`
30	`<div class="noscript-container">`	`Syntax not understood`
31	`<div class="noscript-content">`	`Syntax not understood`
32	`<img`	`Syntax not understood`
33	`src="/_fs-ch-1T1wmsGaOgGaSxcX/assets/errorIcon.svg"`	`Syntax not understood`
34	`alt=""`	`Syntax not understood`
35	`role="presentation"`	`Syntax not understood`
36	`class="error-icon"`	`Syntax not understood`
37	`/>`	`Syntax not understood`
38	`<span class="noscript-span"`	`Syntax not understood`
39	`>JavaScript is disabled in your browser.</span`	`Syntax not understood`
40	`>`	`Syntax not understood`
41	`<p>Please enable JavaScript to proceed.</p>`	`Syntax not understood`
42	`</div>`	`Syntax not understood`
43	`</div>`	`Syntax not understood`
44	`</noscript>`	`Syntax not understood`
45	`<div id="loading-error" role="alert" aria-live="polite">`	`Syntax not understood`
46	`A required part of this site couldn’t load. This may be due to a browser`	`Syntax not understood`
47	`extension, network issues, or browser settings. Please check your`	`Syntax not understood`
48	`connection, disable any ad blockers, or try using a different browser.`	`Syntax not understood`
49	`</div>`	`Syntax not understood`
50	`<script>`	`Syntax not understood`
51	`function loadScript(src) {`	`Syntax not understood`
52	`return new Promise((resolve, reject) => {`	`Syntax not understood`
53	`const script = document.createElement('script');`	`Syntax not understood`
54	`script.onload = resolve;`	`Syntax not understood`
55	`script.onerror = (event) => {`	`Syntax not understood`
56	`console.error('Script load error event:', event);`	`Unknown directive`
57	`document.getElementById('loading-error').style.display = 'block';`	`Syntax not understood`
58	`reject(`	`Syntax not understood`
59	`new Error(`	`Syntax not understood`
60	`Failed to load script: ${src}, Please contact the service administrator.`	`Unknown directive`
61	`)`	`Syntax not understood`
62	`);`	`Syntax not understood`
63	`};`	`Syntax not understood`
64	`script.src = src;`	`Syntax not understood`
65	`document.body.appendChild(script);`	`Syntax not understood`
66	`});`	`Syntax not understood`
67	`}`	`Syntax not understood`
69	`loadScript('/_fs-ch-1T1wmsGaOgGaSxcX/errors.js')`	`Syntax not understood`
70	`.then(() => {`	`Syntax not understood`
71	`const script = document.createElement('script');`	`Syntax not understood`
72	`script.src = '/_fs-ch-1T1wmsGaOgGaSxcX/script.js?reload=true';`	`Syntax not understood`
73	`script.onerror = (event) => {`	`Syntax not understood`
74	`console.error('Script load error event:', event);`	`Unknown directive`
75	`const errorMsg = new Error(`	`Syntax not understood`
76	`Failed to load script: ${script.src}. Please contact the service administrator.`	`Unknown directive`
77	`);`	`Syntax not understood`
78	`console.error(errorMsg);`	`Syntax not understood`
79	`handleScriptError();`	`Syntax not understood`
80	`};`	`Syntax not understood`
81	`document.body.appendChild(script);`	`Syntax not understood`
82	`})`	`Syntax not understood`
83	`.catch((error) => {`	`Syntax not understood`
84	`console.error(error);`	`Syntax not understood`
85	`});`	`Syntax not understood`
86	`</script>`	`Syntax not understood`
87	`</body>`	`Syntax not understood`
88	`</html>`	`Syntax not understood`

To appear in search results, crawlers need access to your app.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links are crawlable

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

Lighthouse Scores

Industry-standard audits powered by Google Lighthouse. — Desktop

Performance

100

Accessibility

100

Best Practices

SEO

Core Web Vitals

Key metrics that affect user experience. — Desktop

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.82 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

2.60 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

91 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.365

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.16 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

2.61 s

Detailed Report

Audit breakdown by category with detailed findings.

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Why this matters

Shipping ES5 transpiled code to modern browsers wastes bytes — every user with an evergreen browser pays for compatibility you don't need.

Learn more ▾

Source: Google web.dev / Lighthouse

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

items: [map[node:map[type:text value:Total] score:0.3650840000000001] map[node:map[boundingRect:map[bottom:7946 height:7309 left:0 right:1350 top:637 width:1350] lhId:page-10-DIV nodeLabel:Khan Academy boosts scores! Learn with millions of people worldwide by explorin… path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV selector:div#app-shell-root > div._keh75d > main#main-content > div._vtegui snippet:<div class="_vtegui"> type:node] score:0.176112 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:615 height:284 left:161 right:560 top:332 width:399] lhId:page-17-IMG nodeLabel:Donate today! path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,2,IMG selector:div._xfcx8w > div._1fwzriw > div > img._5s95i9 snippet:<img alt="Donate today!" class="_5s95i9" src="https://cdn.kastatic.org/ka-mpp/61287d65-adce-475f-a3ab-9a384bc863f8.png"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:7946 height:7309 left:0 right:1350 top:637 width:1350] lhId:page-10-DIV nodeLabel:Khan Academy boosts scores! Learn with millions of people worldwide by explorin… path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV selector:div#app-shell-root > div._keh75d > main#main-content > div._vtegui snippet:<div class="_vtegui"> type:node] score:0.130139 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1254 height:357 left:176 right:695 top:897 width:519] lhId:page-0-IMG nodeLabel:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,IMG selector:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 snippet:<img src="https://cdn.kastatic.org/images/lohp/boost-scores.png" alt="" class="_82vv51"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:7946 height:7309 left:0 right:1350 top:637 width:1350] lhId:page-10-DIV nodeLabel:Khan Academy boosts scores! Learn with millions of people worldwide by explorin… path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV selector:div#app-shell-root > div._keh75d > main#main-content > div._vtegui snippet:<div class="_vtegui"> type:node] score:0.037405 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:615 height:284 left:161 right:560 top:332 width:399] lhId:page-17-IMG nodeLabel:Donate today! path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,1,DIV,0,DIV,1,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,2,IMG selector:div._xfcx8w > div._1fwzriw > div > img._5s95i9 snippet:<img alt="Donate today!" class="_5s95i9" src="https://cdn.kastatic.org/ka-mpp/61287d65-adce-475f-a3ab-9a384bc863f8.png"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:1254 height:357 left:176 right:695 top:897 width:519] lhId:page-0-IMG nodeLabel:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,IMG selector:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 snippet:<img src="https://cdn.kastatic.org/images/lohp/boost-scores.png" alt="" class="_82vv51"> type:node] score:0.005303 subItems:map[items:[map[cause:Unsized image element extra:map[boundingRect:map[bottom:1254 height:357 left:176 right:695 top:897 width:519] lhId:page-0-IMG nodeLabel:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 path:1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,IMG selector:div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 snippet:<img src="https://cdn.kastatic.org/images/lohp/boost-scores.png" alt="" class="_82vv51"> type:node]]] type:subitems]] map[node:map[boundingRect:map[bottom:930 height:409 left:16 right:391 top:521 width:375] lhId:page-14-DIV nodeLabel:Use of cookies Cookies are small files placed on your device that collect infor… path:1,HTML,1,BODY,4,DIV,1,DIV selector:body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk snippet:<div id="onetrust-banner-sdk" class="otFloatingRoundedCorner ot-bottom-left vertical-align-content ot-buttons-fw" tabindex="0" role="region" aria-label="Cookie banner" style="bottom: 1rem;"> type:node] score:0.00055]]

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Top function call valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:31.449 source:map[column:482660 line:21 type:source-location url:https://cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js urlProvider:network]]]

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]

items: [map[reflowTime:8.526 source:map[column:650516 line:20 type:source-location url:https://cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js urlProvider:network]] map[reflowTime:22.923 source:map[column:650634 line:20 type:source-location url:https://cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js urlProvider:network]]]

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG

nodeLabel: div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51

path: 1,HTML,1,BODY,0,DIV,1,DIV,0,DIV,1,DIV,0,DIV,1,DIV,2,MAIN,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,0,DIV,1,IMG

selector: div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51

snippet: <img src="https://cdn.kastatic.org/images/lohp/boost-scores.png" alt="" class="_82vv51">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

title: Preconnected origins

value: no origins were preconnected

description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.

title: Preconnect candidates

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size	Duration
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	771.2 KiB	640 ms
cdn.kastatic.org/khanacademy/khanacademy.753cf3d0cb0bd8f2.css	10.3 KiB	202 ms
cdn.kastatic.org/khanacademy/runtime.d2da0f18e591e2c0.js	13.6 KiB

A long cache lifetime can speed up repeat visits to your page. Learn more about caching.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Request	Cache TTL	Transfer Size
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	86400.0 s	102.8 KiB
cdn.cookielaw.org/logos/static/ot_company_logo.png	86400.0 s	19.1 KiB
cdn.cookielaw.org/scripttemplates/otSDKStub.js	86400.0 s	9.1 KiB
/api/badges/download-on-the-app-store/black/en-us?release...	604800.0 s	11.3 KiB
cdn.cookielaw.org/logos/static/powered_by_logo.svg	86400.0 s	2.7 KiB

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Est Savings
cdn.kastatic.org/khanacademy/fonts/1cf13853095a62e2-LatoLatin-Bold.woff2	10 ms
/khanacademy/fonts/b430c69579ae2887-SourceSerifPro-Semibo...	5.0 ms

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL	Resource Size	Est Savings
Donate today! `div._xfcx8w > div._1fwzriw > div > img._5s95i9`	cdn.kastatic.org/ka-mpp/61287d65-adce-475f-a3ab-9a384bc863f8.png	782.0 KiB	763.6 KiB
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/faces_collage_2@2x.png	666.4 KiB	618.9 KiB
div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 `div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51`	cdn.kastatic.org/images/lohp/boost-scores.png	210.2 KiB	180.0 KiB
div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1 `div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1`	cdn.kastatic.org/images/lohp/laptop_collage@2x.png	181.6 KiB	134.5 KiB
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/empower_teachers_icon.png	9.0 KiB	7.3 KiB
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/personalized_learning_icon.png	8.8 KiB	7.0 KiB
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp`	cdn.kastatic.org/images/lohp/trusted_content_icon.png	9.1 KiB	7.0 KiB
Get it on Google Play `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	cdn.kastatic.org/images/store-badges/google-play/en.png	5.9 KiB	5.7 KiB

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 243 ms

URL	Time Spent
khanacademy.org/	243 ms
www.khanacademy.org/	0.0 ms

Why this matters

Performance issues directly impact user engagement and conversion rates.

Element	Layout shift score
Khan Academy boosts scores! Learn with millions of people worldwide by explorin… `div#app-shell-root > div._keh75d > main#main-content > div._vtegui`	0.176
Khan Academy boosts scores! Learn with millions of people worldwide by explorin… `div#app-shell-root > div._keh75d > main#main-content > div._vtegui`	0.130
Khan Academy boosts scores! Learn with millions of people worldwide by explorin… `div#app-shell-root > div._keh75d > main#main-content > div._vtegui`	0.037
div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 `div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51`	0.005
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.001
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000
Use of cookies Cookies are small files placed on your device that collect infor… `body.lang-en > div#onetrust-consent-sdk > div#onetrust-banner-sdk`	0.000

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Diagnostics

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Multi-megabyte JavaScript bundles delay every interactive feature on the page.

Learn more ▾

Source: Google web.dev / Lighthouse

Estimated savings: 440 ms 577.1 KiB

URL	Transfer Size	Est Savings
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	764.7 KiB	437.0 KiB
www.googletagmanager.com/gtm.js?id=GTM-WSX5PBP	152.2 KiB	86.5 KiB
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	102.7 KiB	53.6 KiB

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reason	Failure type
Pages with cache-control:no-store header cannot enter back/forward cache.	Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.	Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.	Not actionable

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. Learn how to reduce unused CSS.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 0.0 ms 17.0 KiB

URL	Transfer Size	Est Savings
#onetrust-banner-sdk{-ms-text-size-adjust:100%;-webkit-text-size-adjust:100%} …	19.6 KiB	17.0 KiB

Large network payloads cost users real money and are highly correlated with long load times. Learn how to reduce payload sizes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

URL	Transfer Size
cdn.kastatic.org/ka-mpp/61287d65-adce-475f-a3ab-9a384bc863f8.png	782.8 KiB
cdn.kastatic.org/khanacademy/khanacademy.47960f894ea35774.js	771.2 KiB
cdn.kastatic.org/images/lohp/faces_collage_2@2x.png	667.2 KiB
cdn.kastatic.org/images/lohp/last_chance_collage@2x.png	373.9 KiB
cdn.kastatic.org/images/lohp/boost-scores.png	210.6 KiB
cdn.kastatic.org/images/lohp/laptop_collage@2x.png	182.0 KiB
cdn.kastatic.org/images/lohp/math-unicorn-donate-collage.png	158.7 KiB
www.googletagmanager.com/gtm.js?id=GTM-WSX5PBP	152.6 KiB
cdn.cookielaw.org/scripttemplates/202310.2.0/otBannerSdk.js	102.8 KiB
cdn.kastatic.org/images/lohp/anjali-3.png	76.0 KiB

Set an explicit width and height on image elements to reduce layout shifts and improve CLS. Learn how to set image dimensions

Why this matters

Performance issues directly impact user engagement and conversion rates.

	URL
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/faces_collage_2@2x.png
Donate today! `div._xfcx8w > div._1fwzriw > div > img._5s95i9`	cdn.kastatic.org/ka-mpp/61287d65-adce-475f-a3ab-9a384bc863f8.png
div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1 `div._e296pg > div._mg36wky > div._et3ir1 > img._1k6dqj1`	cdn.kastatic.org/images/lohp/laptop_collage@2x.png
div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1 `div._e296pg > div._1b4n03jl > div._hoh1o6o > img._1k6dqj1`	cdn.kastatic.org/images/lohp/math-unicorn-donate-collage.png
div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51 `div._1s6u9f56 > div._8plbkmf > div._1lnhlk8u > img._82vv51`	cdn.kastatic.org/images/lohp/boost-scores.png
Get it on Google Play `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	cdn.kastatic.org/images/store-badges/google-play/en.png
div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1 `div._8iuiziq > div._1wqqgcad > div._46s8e9s > img._1k6dqj1`	cdn.kastatic.org/images/lohp/anjali-3.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._14srqcp`	cdn.kastatic.org/images/lohp/trusted_content_icon.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/personalized_learning_icon.png
div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7 `div._3vgeo5o > div._5hffmqw > div._xnpl0ze > img._zdxht7`	cdn.kastatic.org/images/lohp/empower_teachers_icon.png
Download on the App Store `ul > li._ouyp5ih > a._wilhdph > img._1iym5ly`	/api/badges/download-on-the-app-store/black/en-us?release...

More information about the performance of your application. These numbers don't directly affect the Performance score.

●Optimize DOM size

●LCP breakdown

●Modern HTTP

●Optimize viewport for mobile

●Minify CSS

●Minify JavaScript

●User Timing marks and measures 2 user timings

●JavaScript execution time 0.6 s

●Minimizes main-thread work 1.2 s

●Avoid long main-thread tasks 2 long tasks found

●Avoid non-composited animations 4 animated elements found

●Network Requests

●Network Round Trip Times 190 ms

●Server Backend Latencies 240 ms

●Tasks

●Diagnostics

●Metrics

●Screenshot Thumbnails

●Final Screenshot

●Script Treemap Data

●Resources Summary

●Initial server response time was short Root document took 230 ms

○INP breakdown

100

Accessibility

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
English `div._s6za34 > div._1bvnlzk > div._6kyiev1 > button#:r6:`
cookie policy `div#onetrust-group-container > div#onetrust-policy > div#onetrust-policy-text > a`

○Interactive controls are keyboard focusable

○Interactive elements indicate their purpose and state

○The page has a logical tab order

○Visual order on the page follows DOM order

○User focus is not accidentally trapped in a region

○The user's focus is directed to new content added to the page

○HTML5 landmark elements are used to improve navigation

○Offscreen content is hidden from assistive technology

○Custom controls have associated labels

○Custom controls have ARIA roles

●`[aria-*]` attributes match their roles

●`[aria-hidden="true"]` is not present on the document `<body>`

●`[role]`s have all required `[aria-*]` attributes

●`[role]` values are valid

●`[aria-*]` attributes have valid values

●`[aria-*]` attributes are valid and not misspelled

●Buttons have an accessible name

●Image elements have `[alt]` attributes

●Form elements have associated labels

●`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.

●ARIA attributes are used as specified for the element's role

●Elements with `role="dialog"` or `role="alertdialog"` have accessible names.

●`[aria-hidden="true"]` elements do not contain focusable descendents

●Elements use only permitted ARIA attributes

●Background and foreground colors have a sufficient contrast ratio

●Document has a `<title>` element

●`<html>` element has a `[lang]` attribute

●`<html>` element has a valid value for its `[lang]` attribute

●Links are distinguishable without relying on color.

●Links have a discernible name

●Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).

●List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements

●No element has a `[tabindex]` value greater than 0

●Touch targets have sufficient size and spacing.

●Heading elements appear in a sequentially-descending order

●Document has a main landmark.

●Deprecated ARIA roles were not used

●Identical links have the same purpose.

○`[accesskey]` values are unique

○`button`, `link`, and `menuitem` elements have accessible names

○ARIA input fields have accessible names

○ARIA `meter` elements have accessible names

○ARIA `progressbar` elements have accessible names

○Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.

○`[role]`s are contained by their required parent element

○Elements with the `role=text` attribute do not have focusable descendents.

○ARIA toggle fields have accessible names

○ARIA `tooltip` elements have accessible names

○ARIA `treeitem` elements have accessible names

○The page contains a heading, skip link, or landmark region

○`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.

○Definition list items are wrapped in `<dl>` elements

○ARIA IDs are unique

○No form fields have multiple labels

○`<frame>` or `<iframe>` elements have a title

○`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.

○Input buttons have discernible text.

○`<input type="image">` elements have `[alt]` text

○The document does not use `<meta http-equiv="refresh">`

○`<object>` elements have alternate text

○Select elements have associated label elements.

○Skip links are focusable.

○Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.

○`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.

○`[lang]` attributes have a valid value

○`<video>` elements contain a `<track>` element with `[kind="captions"]`

○Tables have different content in the summary attribute and `<caption>`.

○All heading elements contain content.

○Uses ARIA roles only on compatible elements

○Image elements do not have `[alt]` attributes that are redundant text.

○Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.

○`<td>` elements in a large `<table>` have one or more table headers.

100

Best Practices

●Uses HTTPS

●Avoids deprecated APIs

●Avoids third-party cookies

●Allows users to paste into input fields

●Avoids requesting the geolocation permission on page load

●Avoids requesting the notification permission on page load

●Displays images with correct aspect ratio

●Serves images with appropriate resolution

●Page has the HTML doctype

●Properly defines charset

●No browser errors logged to the console

●No issues in the `Issues` panel in Chrome Devtools

●Ensure CSP is effective against XSS attacks

●Ensure proper origin isolation with COOP

●Mitigate DOM-based XSS with Trusted Types

●Page has valid source maps

○Redirects HTTP traffic to HTTPS

○Use a strong HSTS policy

○Mitigate clickjacking with XFO or CSP

○Detected JavaScript libraries

SEO

Content Best Practices

Descriptive link text helps search engines understand your content. Learn how to make links more accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Link destination	Link Text
cookiepedia.co.uk/giving-consent-to-cookies	More information

Format your HTML in a way that enables crawlers to better understand your app’s content.

Crawling and Indexing

If your robots.txt file is malformed, crawlers may not be able to understand how you want your website to be crawled or indexed. Learn more about robots.txt.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Line #	Content	Error
1	`<!DOCTYPE html>`	`Syntax not understood`
2	`<html lang="en">`	`Syntax not understood`
3	`<head>`	`Syntax not understood`
4	`<meta`	`Syntax not understood`
5	`http-equiv="Content-Security-Policy"`	`Syntax not understood`
6	`content="default-src 'self'; img-src 'self' data:; media-src 'self' data:; object-src 'none'; style-src 'self' 'sha256-o4vzfmmUENEg4chMjjRP9EuW9ucGnGIGVdbl8d0SHQQ='; script-src 'self' 'sha256-a9bHdQGvRzDwDVzx8m+Rzw+0FHZad8L0zjtBwkxOIz4=';"`	`Unknown directive`
7	`/>`	`Syntax not understood`
8	`<link`	`Syntax not understood`
9	`href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/inter-var.woff2"`	`Syntax not understood`
10	`rel="preload"`	`Syntax not understood`
11	`as="font"`	`Syntax not understood`
12	`type="font/woff2"`	`Syntax not understood`
13	`crossorigin`	`Syntax not understood`
14	`/>`	`Syntax not understood`
15	`<link href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/styles.css" rel="stylesheet" />`	`Syntax not understood`
16	`<meta name="viewport" content="width=device-width, initial-scale=1" />`	`Syntax not understood`
17	`<title>Client Challenge</title>`	`Syntax not understood`
18	`<style>`	`Syntax not understood`
20	`font-size: 16px;`	`Unknown directive`
21	`font-family: 'Inter', sans-serif;`	`Unknown directive`
22	`margin-top: 10px;`	`Unknown directive`
23	`margin-left: 10px;`	`Unknown directive`
24	`display: none;`	`Unknown directive`
25	`}`	`Syntax not understood`
26	`</style>`	`Syntax not understood`
27	`</head>`	`Syntax not understood`
28	`<body>`	`Syntax not understood`
29	`<noscript>`	`Syntax not understood`
30	`<div class="noscript-container">`	`Syntax not understood`
31	`<div class="noscript-content">`	`Syntax not understood`
32	`<img`	`Syntax not understood`
33	`src="/_fs-ch-1T1wmsGaOgGaSxcX/assets/errorIcon.svg"`	`Syntax not understood`
34	`alt=""`	`Syntax not understood`
35	`role="presentation"`	`Syntax not understood`
36	`class="error-icon"`	`Syntax not understood`
37	`/>`	`Syntax not understood`
38	`<span class="noscript-span"`	`Syntax not understood`
39	`>JavaScript is disabled in your browser.</span`	`Syntax not understood`
40	`>`	`Syntax not understood`
41	`<p>Please enable JavaScript to proceed.</p>`	`Syntax not understood`
42	`</div>`	`Syntax not understood`
43	`</div>`	`Syntax not understood`
44	`</noscript>`	`Syntax not understood`
45	`<div id="loading-error" role="alert" aria-live="polite">`	`Syntax not understood`
46	`A required part of this site couldn’t load. This may be due to a browser`	`Syntax not understood`
47	`extension, network issues, or browser settings. Please check your`	`Syntax not understood`
48	`connection, disable any ad blockers, or try using a different browser.`	`Syntax not understood`
49	`</div>`	`Syntax not understood`
50	`<script>`	`Syntax not understood`
51	`function loadScript(src) {`	`Syntax not understood`
52	`return new Promise((resolve, reject) => {`	`Syntax not understood`
53	`const script = document.createElement('script');`	`Syntax not understood`
54	`script.onload = resolve;`	`Syntax not understood`
55	`script.onerror = (event) => {`	`Syntax not understood`
56	`console.error('Script load error event:', event);`	`Unknown directive`
57	`document.getElementById('loading-error').style.display = 'block';`	`Syntax not understood`
58	`reject(`	`Syntax not understood`
59	`new Error(`	`Syntax not understood`
60	`Failed to load script: ${src}, Please contact the service administrator.`	`Unknown directive`
61	`)`	`Syntax not understood`
62	`);`	`Syntax not understood`
63	`};`	`Syntax not understood`
64	`script.src = src;`	`Syntax not understood`
65	`document.body.appendChild(script);`	`Syntax not understood`
66	`});`	`Syntax not understood`
67	`}`	`Syntax not understood`
69	`loadScript('/_fs-ch-1T1wmsGaOgGaSxcX/errors.js')`	`Syntax not understood`
70	`.then(() => {`	`Syntax not understood`
71	`const script = document.createElement('script');`	`Syntax not understood`
72	`script.src = '/_fs-ch-1T1wmsGaOgGaSxcX/script.js?reload=true';`	`Syntax not understood`
73	`script.onerror = (event) => {`	`Syntax not understood`
74	`console.error('Script load error event:', event);`	`Unknown directive`
75	`const errorMsg = new Error(`	`Syntax not understood`
76	`Failed to load script: ${script.src}. Please contact the service administrator.`	`Unknown directive`
77	`);`	`Syntax not understood`
78	`console.error(errorMsg);`	`Syntax not understood`
79	`handleScriptError();`	`Syntax not understood`
80	`};`	`Syntax not understood`
81	`document.body.appendChild(script);`	`Syntax not understood`
82	`})`	`Syntax not understood`
83	`.catch((error) => {`	`Syntax not understood`
84	`console.error(error);`	`Syntax not understood`
85	`});`	`Syntax not understood`
86	`</script>`	`Syntax not understood`
87	`</body>`	`Syntax not understood`
88	`</html>`	`Syntax not understood`

To appear in search results, crawlers need access to your app.

○Structured data is valid

●Page isn’t blocked from indexing

●Document has a `<title>` element

●Document has a meta description

●Page has successful HTTP status code

●Links are crawlable

●Image elements have `[alt]` attributes

●Document has a valid `hreflang`

●Document has a valid `rel=canonical`

Results for https://khanacademy.org

Site Health

How you compare

Top Priorities (5)

Fix Priority Matrix

Quick Wins

Strategic

Easy Improvements

Deprioritize

What fixing these means

Return on Investment

Investment

Monthly returns

Regulatory risk avoided

Payback period

Estimated Remediation Cost

Cost by category

Cost by effort level

What Inaction Is Costing You

Compliance Risk

Bandwidth Waste

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Best Practices

SEO

Content Best Practices

Crawling and Indexing

Lighthouse Scores

Core Web Vitals

Detailed Report

Performance

Insights

Diagnostics

Accessibility

Best Practices

SEO

Content Best Practices

Crawling and Indexing

Keyboard Shortcuts